GDDS-V1.2
An Open Source
G
NSS
D
ata
D
ownload
S
oftware
User Manual
Sat April 10 12:38:06 UTC 2024
GDDS User Manual
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Contents
1 Before You Start ....................................................................................................... 1
1.1 End-User License Agreement .......................................................................................... 1
1.2 Scope of Operation .......................................................................................................... 1
1.3 Contact Us ....................................................................................................................... 2
1.4 Bug Reports/Comments................................................................................................... 2
1.5 Version History ............................................................................................................... 2
2 Software Instructions................................................................................................ 3
2.1 Software Acquisition ....................................................................................................... 3
2.2 Software Installation ........................................................................................................ 3
2.3 Module Introduction ........................................................................................................ 4
3 Operation Module ..................................................................................................... 6
3.1 “Global IGS data” Module .............................................................................................. 6
3.1.1 File Type ................................................................................................................... 6
3.1.2 Time Range .............................................................................................................. 6
3.1.3 IGS Station ............................................................................................................... 7
3.1.4 Data Center ............................................................................................................... 8
3.1.5 Output Path ............................................................................................................... 9
3.1.6 Function Button ........................................................................................................ 9
3.2 “Post-Processing Product” Module ................................................................................. 9
3.2.1 Institution .................................................................................................................. 9
3.2.2 Product Type .......................................................................................................... 11
3.2.3 Time Range ............................................................................................................ 11
3.2.4 Output Path ............................................................................................................. 12
3.2.5 Function Button ...................................................................................................... 12
3.3 “Regional CORS Data” Module .................................................................................... 12
3.3.1 CORS Source.......................................................................................................... 12
3.3.2 File Type ................................................................................................................. 13
3.3.3 Time Range ............................................................................................................ 13
3.3.4 CORS Station ......................................................................................................... 13
3.3.5 Output Path ............................................................................................................. 15
3.3.6 Function Button ...................................................................................................... 15
3.4 “Time Series Product” Module ..................................................................................... 15
3.4.1 Institution ................................................................................................................ 16
3.4.2 File Type ................................................................................................................. 16
3.4.3 Time Range ............................................................................................................ 17
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3.4.4 Station ..................................................................................................................... 17
3.4.5 Output Path ............................................................................................................. 17
3.4.6 Function Button ...................................................................................................... 17
3.5 “Custom Download” Module ........................................................................................ 17
3.5.1 URL Templates ...................................................................................................... 18
3.5.2 Setting Protocol ...................................................................................................... 18
3.5.3 Setting Domain Name ............................................................................................ 18
3.5.4 Setting File Directory ............................................................................................. 18
3.5.5 Setting File Name ................................................................................................... 18
3.5.6 Output Path ............................................................................................................. 19
3.5.7 Time Span and Site ................................................................................................. 19
3.5.8 Function Button ...................................................................................................... 19
3.6 “Data Decompression” Module ..................................................................................... 19
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1 Before You Start
1.1 End-User License Agreement
Copyright
©
2023 ECUT (East China University of Technology). All rights reserved.
GDDS (GNSS Data Download Software) can be used under the following license
conditions:
1. With this license, the copyright holder ECUT permits to use the software GDDS
free of charge in executable form and for non-commercial purposes only.
2. Unless expressly stated in this license, you may not copy, modify, sublicense,
distribute or create any derivate works of the software. Any attempt to copy, modify,
sublicense, or distribute the program in other ways is void and will automatically
terminate your rights under this license.
3. The software is provided “as is” without any express or implied guarantees,
including but not limited to the implied warranties of merchantability and fitness
for some particular purpose. All risks as to the quality and performance of the
program are with you. Should the program prove defective, you assume the cost of
all necessary maintenance, repair, or correction.
4. Under no circumstances, unless required by applicable law or written consent, the
copyright holder shall not be responsible for your damages, including any general,
special, incidental, or consequential damages (including but not limited to data
inaccuracies or losses due to third parties, or failures to operate with any other
procedures), even if the holder has been informed of the possibility of such
damages.
5. This clause shall be governed, interpreted, and enforced by the laws of the People’s
Republic of China.
1.2 Scope of Operation
The GDDS is software for GNSS data download, which provides an interactive
interface for the Windows or Linux operating system. The following GNSS data types
are supported to download:
● Observation data
● Navigation data
● Meteorology data
Post-processing product (i.e., precise ephemeris, precise clock, troposphere, global
ionosphere maps, ionospheric spherical harmonic model, rate of TEC index,
antenna phase center model, earth rotation parameters, satellite attitude
information, satellite yaw information, differential code bias, bias-SINEX, and
daily/weekly solution)
● Time series products
The following operations/tasks are supported:
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● Time transformation
● Map-based IGS/CORS station selection
● Station information inquiry
● IGS/CORS station display
● Data download customization
● Data decompression
1.3 Contact Us
There is an e-mail address lglu66@163.com for information transfer (new features,
versions, etc.) or prompt answer not included in the documentation.
1.4 Bug Reports/Comments
For bug reports or comments, please contact the email address lglu66@163.com.
Please follow the procedure below for bug reports:
● Make sure to use the latest version.
● If you are using the latest version, please provide complete download information
settings.
● Try to offer a detailed description of the problem generation process. If possible,
please attach a screenshot of the GDDS interface to your e-mail.
1.5 Version History
2024-4-10 (V1.2)
The software has updated URL addresses for some products and data that are
invalid
The software has added a time series product download module
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2 Software Instructions
2.1 Software Acquisition
Any group or individual can contact the email address
lglu66@163.com
to apply for
the latest version of GDDS free of charge. Please indicate the applicant's information
and software purpose in the email.
2.2 Software Installation
After downloading and opening the “GDDS.zip” software package, users can obtain
the “Windows.zip” and “Linux.zip” version compressed files in the bin folder, which
contains the running environment and executable program of the software. After
decompressing the required version file, users can find the executable program
“GDDS.exe” and double-click it to run without installation. It is recommended to close
the anti-virus software to avoid deleting the executable file by mistake.
Fig. 2.1
Example of executable file storted in “\GDDS\bin\Windows\GDDS.exe”
After double-clicking “GDDS.exe”, the software will start to run. The main interface
of the software is shown in Fig. 2.2.
Fig. 2.2
Software main interface
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2.3 Module Introduction
GDDS consists of six modules, i.e., Global IGS data, Post-Processing Product,
Regional CORS data, Time Series Product, Custom Download, and Data
Decompression. Among them, the first four modules are used to download various
GNSS data and products shown in Table 1. “Custom Download” module can execute
the download link of user-defined configuration. The last module supports batch
decompression of UNIX compressed files (with Z, gz as extensions) and CRINEX files
(with d, crx as extensions).
Table 1
Download content corresponding to different modules of GDDS
Module
Download source
File type
Global IGS data
1.WHU (China)
2.IGN (France)
3.ESA (Europe)
4.KASI (Korea)
5.SIO (USA)
6.CDDIS (USA)
1.RINEX 2.11/3.xx observation data (o/mo)
2.RINEX 2.11/3.xx meteorology data (m/mm)
3.RINEX 2.xx/3.xx navigation data (n/mn)
Post-Processing Product
1.IGS
2.JPL (USA)
3.MIT (USA)
4.ESA (Europe)
5.GRG (France)
6.CAS (China)
7.UPC (Spain)
8.CODE
(Switzerland)
9.SIO (USA)
10.NGS (USA)
11.EMR (Canada)
12.GFZ (Germany)
13.WHU (China)
1.Precise ephemeris (sp3/eph)
2.Precise clock (clk)
3.Satellite yaw information (yaw)
4.Earth rotation parameters (erp)
5.Satellite attitude information (obx)
6.Antenna phase center model (atx)
7.Troposphere (tro/zpd)
8.Ionospheric-spherical harmonic model (ion)
9.Global ionosphere maps (i)
10.Rate of TEC index (f)
11.Differential code bias (dcb)
12.OSB Bias-SINEX (bia)
13.REL Bias-SINEX (bia)
14.DCB Bias-SINEX (bsx)
15.Daily/Weekly solution (snx)
Regional CORS data
1.USA CORS
2.Europe EPN
3.Spain CORS
4.Japan JPN
5.HongKong CORS
1.RINEX 2.11/3.xx observation data (o/mo)
2.RINEX 2.11/3.xx meteorology data (m/mm)
3.RINEX 2.xx/3.xx navigation data (n/mn)
4.Partial products
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6.Curtin University
7.Australia APREF
Time Series Product
1.EQDSC (China)
2.NGL (USA)
3.SOPAC (USA)
4.UNAVCO (USA)
5.IERS (Global)
1.Combine time series (tar)
2.Time series (txt)
3.Residue time series (dat)
4.IGS14_XYX (txyz2)
5.IGS14_NEU (tenv3)
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3 Operation Module
3.1 “Global IGS data” Module
The “Global IGS data” module mainly downloads GNSS data provided by the IGS data
centers. You can click the “Global IGS data” button in the GDDS main interface to run
this module. The “Global IGS data” operation interface is shown in Fig. 3.1.
Fig. 3.1
“Global IGS data” operation interface
3.1.1 File Type
The file types supported in this module are mainly observation data, navigation data,
and meteorology data of RINEX version 2.11 and 3. xx provided by the IGS data center.
You can choose to download one or more file types as needed. Since observation data
and meteorology data are related to IGS stations, the corresponding IGS station needs
to be added in the subsequent process when this file type is selected.
3.1.2 Time Range
Then set the start and end time corresponding to the download file. You can select one
of any three different modes to express time, such as Year-Month-Day (Year-Month-
Day Hour-Minute, Year-Month-Day Hour), Year with DOY, GPS week with Day of
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week. The software will automatically switch to the other two according to the input
mode, which is convenient for users. It should be noted that the data released by IGS
has a certain lag, so when setting the start and end time, you can move forward slightly
at the current time.
3.1.3 IGS Station
When the observation data or meteorology data is selected in the file type, it is also
necessary to choose and add the corresponding IGS station. The interface of the IGS
station is illustrated in Fig. 3.2 below.
Fig. 3.2
IGS station interface
On the left is the text box for searching and selecting the target IGS station.
Stations displayed in this session will be updated in real-time according to the file type
in order to ensure effectiveness and correctness. If you have specific requirements for
the IGS station name, you can search for the station name based on this part and select
the corresponding station name.
The text box on the right is a collection of the selected station information. The
corresponding station for the final data download should be subject to the one shown in
this part. You can add, modify and delete station information in here.
In the middle are some function buttons. The “Map Choose” button can open the
map interaction function, which not only displays the global distribution of IGS stations
but also supports a variety of interactive functions, such as single station selection,
frame selection (i.e., rectangle, polygon, and circle), distance measurement, area
calculation, etc. IGS map interactive function is exhibited in Fig. 3.3.
The “Info Inquire” button will generate the station information table, which is used
to query some basic information of the IGS station, such as coordinates (longitude and
latitude), receiver type, antenna type, etc, and support the operation of modifying,
adding, deleting, exporting, saving and restoring the content of the station information
table. IGS information retrieval function is displayed in Fig. 3.4.
The Add Station” button can add the selected station on the left to the text box on
the right. The “Map Display” button displays the selected stations in the right-hand text
box on the map. The “Clear Station” is to quickly clear all stations in the text box on
the right.
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Fig. 3.3
IGS map interactive function interface
Fig. 3.4
IGS information retrieval function interface
3.1.4 Data Center
The download sources supported by this module are six global data centers of IGS,
namely WHU in China, IGN in France, ESA in Europe, CDDIS in the United States,
SIO in the United States, and KASI in Korea. Users from different countries can choose
the appropriate data center here to achieve the best download speed.
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3.1.5 Output Path
Finally, select the output path of the download file. The default output path is the
“Download folder on the computer desktop. You can also set other output paths as
needed. Note that if the output path does not exist in the computer, the software will
automatically create a corresponding folder according to the input path.
3.1.6 Function Button
There is a row of function buttons at the bottom of the module, namely “Download”,
“Detail”, “Open” and “Help”. The “Download” button is used to start the download
task. The “detail” button aims to open the log file of the entire download task, which
also contains the analysis of the failure download task. The “Open” button can be
devoted to conveniently the download folder open. The “Help” button is to quickly
open the “GDDS User Manual” file.
3.2 “Post-Processing Product” Module
The “Post-Processing Product” module mainly downloads GNSS products provided by
the IGS analysis center and other relevant data computation institutions. You can click
the “Post-Processing Product” button in the GDDS main interface to run the module.
The interface of this module is shown in Fig. 3.5.
Fig. 3.5
“Post-Processing Product” operation interface
3.2.1 Institution
Different institutions have their own post-processing products, which can be found on
their own websites as well as on the websites of other institutions for data sharing
reasons. Therefore, in the post-processing product module, users can choose different
websites to download products. The URLs supported by different institutions are shown
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in Table 2.
Table 2
Available URLs for products provided by different institutions
Institution
URL
IGS
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gps/products/
http://garner.ucsd.edu
/pub/products/
CODE
http://ftp.aiub.unibe.ch/
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gps/products/
http://garner.ucsd.edu
/pub/products/
CAS
ftp://182.92.166.182/product/
ftp://ftp.gipp.org.cn/product/
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
WHU
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://igs.gnsswhu.cn/pub/whu/
ftp://gssc.esa.int/gnss/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
GFZ
ftp://ftp.gfz-potsdam.de/GNSS/products/
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gnss/products/
http://garner.ucsd.edu
/pub/products/
ESA
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gps/products/
http://garner.ucsd.edu
/pub/products/
JPL
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gps/products/
http://garner.ucsd.edu
/pub/products/
MIT
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
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ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gps/products/
http://garner.ucsd.edu
/pub/products/
GRG
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gps/products/
EMR
ftp://rtopsdata1.geod.nrcan.gc.ca/gps/products/
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/'
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gps/products/
SIO
http://garner.ucsd.edu/pub/products/
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gps/products/
NGS
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
ftp://igs.ensg.ign.fr/pub/igs/products/
ftp://nfs.kasi.re.kr/gps/products/
UPC
ftp://gssc.esa.int/gnss/products/
ftp://igs.gnsswhu.cn/pub/gps/products/
ftp://gdc.cddis.eosdis.nasa.gov/pub/gps/products/
3.2.2 Product Type
The product types supported by this module include precise ephemeris (.sp3/.eph),
precise clock (.clk), satellite yaw information (.yaw), earth rotation parameters (.erp),
satellite attitude information (.obx), antenna phase center model (.atx), troposphere
(.tro/.zpd), ionospheric spherical harmonic model (.ion), global ionosphere maps (.i),
rate of TEC index (.f), differential code bias (.dcb), bias-SINEX (.bia), and daily/weekly
solution (.snx). There are differences in the types of products provided by different
institutions (Tips: G/R is GPS/GLONASS, MGEX is multi-GNSS, and unstatement is
GPS/GLONASS).
3.2.3 Time Range
Similarly, set the start and end time corresponding to the download file. As mentioned
above, you can select any one of the three modes to express time, and then the software
will automatically realize time conversion. Please note that those products provided by
institutions have a certain lag, so it is suggested to move forward slightly at the current
time when setting the start and end times.
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3.2.4 Output Path
Choose the output path of the download files. The default output path is the “Download”
folder on the computer desktop. You can also set another output path as required. When
the output path does not exist in the computer, the software will automatically create
the corresponding folder according to the input path.
3.2.5 Function Button
There is a row of function buttons below this module, namely “Download”, “Detail”,
“Open”, and “Help”. Each function is similar to the previous section.
3.3 “Regional CORS Data” Module
The “Regional CORS Data” module mainly downloads GNSS data and partial products
provided by CORS. You can click the “Regional CORS Data” button in the GDDS main
interface to run this module. The interface of this module is shown in Fig. 3.6.
Fig. 3.6
“Regional CORS Data” operation interface
3.3.1 CORS Source
The download sources supported by this module are CORS, namely American CORS,
Australian APREF, European EPN, Spanish CORS, Hong Kong CORS, and Curtin
University. You can select data and products from different CORS to download
according to your needs.
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3.3.2 File Type
The file types supported by this module include observation data, navigation data,
meteorology data, and some products (such as precise ephemeris, precise clock, small
cycle slip, and weekly solution). Different CORS provides different file types.
3.3.3 Time Range
As is stated above, you can set the start and end time in any of three ways, and then the
software automatically realizes time transformation. It should be noted that those data
provided by CORS have a certain lag, so when setting the start and end time, please
move forward slightly at the current time.
3.3.4 CORS Station
When selecting the observation or meteorology data, you also need to choose and add
the corresponding CORS station. The interface design of the CORS station is divided
into three parts, as shown in Fig. 3.7.
Fig. 3.7
CORS station interface display
On the left is the text box for searching and selecting the target CORS station.
Stations displayed here will be updated in real-time based on the selected file type and
the CORS source. When you have specific requirements for CORS station name, you
can search for the station name and then select the corresponding station.
The text box on the right is a summary of the added CORS station information.
The corresponding station for the final data download should be according to the one
shown in this part, and it can also be added, modified, and deleted in here.
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Fig. 3.8
American CORS map interactive function interface
In the middle are some function buttons. The “Map Choose” button can implement
the map interaction function, which not only shows the global distribution of CORS
stations but also supports various interactive functions, such as single station selection,
frame selection (namely rectangle, polygon, circle), distance measurement, area
calculation, etc. Take the American CORS map interactive function as an example, as
exhibited in Fig. 3.8.
The “Info Inquire” button can create the station information table to query some
basic information of the CORS station, such as the station coordinates (longitude and
latitude), receiver type, and antenna type, and support the operation of modifying,
adding, deleting, exporting, saving and restoring the content of the station information
table. Take the American CORS information retrieval function as an example, and the
software interface is displayed in Fig. 3.9.
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Fig. 3.9
American CORS information retrieval function interface
The “Add Station” button adds the selected station on the left to the text box on
the right. The “Map Display” button intuitively displays CORS stations in the right-
hand text box on the map. The “Clear Station” is to quickly clear all stations in the text
box on the right.
3.3.5 Output Path
As commented earlier, you can use the default output path on the computer desktop or
set another appropriate output path.
3.3.6 Function Button
Function buttons at the bottom of this module are the same as described above, not tired
in words here.
3.4 “Time Series Product” Module
The “Time Series Product” module mainly downloads GNSS time series product
provided by some research institutions. You can click the “Time Series Product” button
in the GDDS main interface to run the module. The interface of this module is shown
in Fig. 3.10.
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Fig. 3.10
“Time Series Product” operation interface
3.4.1 Institution
The download sources supported by this module are China EQDSC, USA NGL, USA
SOPAC, USA UNAVCO, and IERS. You can select data and products from different
research institutions to download according to your needs. The URLs supported by
different institutions are shown in Table 3.
Table 3
Available URLs for time series products provided by different institutions
Institution
URL
EQDSC
https://www.eqdsc.com/eastern/upload/gnss/kssjxl/ys/
NGL
http://geodesy.unr.edu/gps_timeseries/
http://geodesy.unr.edu/tsplots/
S
OPAC
ftp://sopac
-
ftp.ucsd.edu/pub/timeseries/measures/
UNAVCO
https://geodesy.noaa.gov/corsdata/coord/
IERS
https://itrf.ign.fr/ftp/pub/itrf/
3.4.2 File Type
The file types supported by this module include combine time series, time series,
residue time series, IGS14_XYX, and IGS14_NEU. Different research institutions
provide different file types.
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3.4.3 Time Range
As is stated above, you can set the start and end time in any of three ways, and then the
software automatically realizes time transformation. It should be noted that those data
provided by research institutions have a certain lag, so when setting the start and end
time, please move forward slightly at the current time.
3.4.4 Station
When downloading time series products, some institution's sources must also add
station information.
3.4.5 Output Path
As commented earlier, you can use the default output path on the computer desktop or
set another appropriate output path.
3.4.6 Function Button
Function buttons at the bottom of this module are the same as described above, not tired
in words here.
3.5 “Custom Download” Module
The “Custom Download” module mainly realizes the download of data according to
the download link configured by the user. You can click the “Custom Download” button
on the main interface of GDDS to start the module. The interface of this module is
shown in Fig. 3.11.
Fig. 3.11
“Custom Download” operation interface
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3.5.1 URL Templates
Display the actual details of the self-configured URL in real time, and open the
information setting interface through the “Settings” button to modify, add, delete and
restore it..
3.5.2 Setting Protocol
Select the protocol type corresponding to the target data transmission. There are mainly
three protocol types: ftp, http and https.
3.5.3 Setting Domain Name
Select or add the domain name of the server where the target data is stored.
3.5.4 Setting File Directory
Enter the specific storage path of the target data in the server. When the path contains
variables such as time and station name, you need to refer to the label for input. For
details of the supported labels, see “Label Explanation” at the bottom of the software.
3.5.5 Setting File Name
Enter the file name corresponding to the target data. For the convenience of users, the
file names of most file types are provided in “Common Template”, including RINEX
V3, RINEX V2 and Product. The explains of common template of file name are listed
in Table 4.
Table 4
The explains of common template of file name
File name template Letters
Meaning
<SITE>RNCRC_S_<year4><doy>
HRMN_LEN_FRQ_ST.FMT
RN The number of the receiver;
CRC
A three-digit ISO-3166-1 standard country
code that identifies the site location;
S
Data source, that is, the data comes from
the receiver (R) or the data stream (S);
HRMN
Observation start time: hour, minute;
LEN The length of the observation period;
FRQ
Sampling interval or sampling frequency
during observation (no such item in
ephemeris file);
ST
Included satellite system and data type, the
first digit indicates the satellite system (M,
G, R, C, E, J, I); the second digit is the data
type, namely observation file (O),
navigation file (N) or Meteorological file
(M);
FMT
There are only two types of extensions:
rnx or crx
;
<site><doy>#.<year2>t #
1 bit, when there are multiple files in a day,
it indicates the number of files in a day.
Usually 0 means all data for a day (one
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file);
t type of data;
AAA<week><dow>.TYP
AAA The name of analysis center;
TYP type of solution;
3.5.6 Output Path
Select the output path for the downloaded file. The default output path is the Downloads
folder on your computer desktop. You can also set to other output paths as needed. Tip:
When the folder displayed in the text box does not exist on the computer, the software
will automatically create the folder.
3.5.7 Time Span and Site
Set the time corresponding to the time tag in the download link. You can set three time
formats: year-month-day, year-year cumulative day, GPS week and day of the week,
the software will automatically convert the other two times according to the time you
input, and customize the time in the download link The label is replaced with a specific
time.
Set the specific station corresponding to the station label in the download link. This
action is not required when the configured download link does not contain a station tag.
3.5.8 Function Button
There are some function buttons under the module, namely “Generate URL”,
“Download”, “Open Dir” and “Detail”. “Generate URL” is to generate a specific URL
according to the various information configured in the above steps, and the generated
URL will be loaded and displayed in the left text box; “Download” is to execute the
download task corresponding to the URL in the left text box of the button; “Open Dir”
is to switch the output path of the open file; “Detail” is to view the execution of the task.
3.6 “Data Decompression” Module
The “Data Decompression” module supports the decompression of GNSS data and
products. Based on this module, UNIX compressed files (with Z, gz as extensions) and
CRINEX files (with d, crx as extensions) can be decompressed in batch with “one-
click”.